Field of the Invention
This invention relates to a backplane connector assembly consisting of a printed circuit board connector which is matable with connectors mounted to a daughterboard extending at right angles to the motherboard and provides for distribution of both power and signal from the motherboard to the daughterboard.
Description of the Prior Art
Backplane systems consisting of a backplane or motherboard to which a plurality of orthogonally oriented daughterboards conventionally employ a plurality of connectors to distribute both current and power from the single motherboard or backplane to the plurality of daughterboards. Both the motherboard and the daughterboards generally require a large number of conductive traces employed on the printed circuit board substrate, and it is quite common for the motherboard to be a multilayer printed circuit board. In any event, a large number of both signal and power contacts are commonly employed to make the necessary interconnections between the motherboard and the daughterboard.
U.S. Pat. No. 4,655,518 discloses a backplane/daughterboard connector in which a two-part connector assembly is used to interconnect corresponding traces on the motherboard and the daughterboard. The connector assembly used to interconnect the motherboard to individual daughterboards consists of a two-part member, each part having a plastic housing in a plurality of rows of contacts. Contacts in one connector have receptacle portions for mating with pins in the other connector. This connector also employs a ground shield on both connector halves. A commercial version of a connector of this type also provides for the distribution of power from the motherboard by the use of special dedicated power tuning fork contacts located on the end of connector modules. These tuning fork contacts in the daughterboard connector interface with bus blades which, in turn, interface with the backplane or daughterboard inner layers for low power applications and with external bus bars for higher power operations.
Connectors of this type also employ a plurality of rows of signal contacts. In one embodiment, four rows of signal contacts are employed. Ground planes are necessary so that the impedance for the signal interconnections remain within prescribed limits.